1. Field of the Invention
The present invention relates to an ultrasound treatment instrument that performs treatment such as dissection, ablation, or coagulation of living tissue by using ultrasound.
2. Description of the Related Art
Conventionally, as a treatment instrument for performing surgical treatment, an ultrasound treatment instrument has been known. An ultrasound treatment instrument is capable of performing treatment such as dissection, ablation, or coagulation of living tissue, for example, by transmitting ultrasound vibration to the living tissue, or merging ultrasound vibration and a high-frequency current and transmitting the ultrasound vibration and the high-frequency current.
In particular, as an ultrasound treatment instrument favorable for fine and delicate surgical treatment such as thyroidectomy, among ultrasound treatment instruments, a forceps type (scissors type) ultrasound treatment instrument is disclosed in for example, Japanese Patent Application Laid-Open Publication No. 2009-514566. The forceps type ultrasound treatment instrument has a treatment instrument main body (handle assembly) containing a waveguide (transmission rod) that transmits ultrasound vibration to a distal end side from a proximal end side, and a clamp arm that is pivotally supported swingably at the treatment instrument main body via a shaft portion. From a distal end of the treatment instrument main body, an ultrasound probe (blade) that is a distal end portion of the waveguide is protruded. A bent portion for avoiding interference with the treatment instrument main body is provided at a distal end side of the clamp arm that intersects the treatment instrument main body via the shaft portion. A jaw (clamp member) for sandwiching living tissue between the jaw and the ultrasound probe is provided at a distal end side from the bent portion. Further, the jaw is provided with a pad formed from a resin or the like, in a region contactable with the ultrasound probe.